Based on the photorefractive self-bending successive four-wave mixing interaction theory, a computational model of mutually pumped phase conjugation (MPPC) with multiple coupled interaction regions is proposed to analyze the output characteristics under an electronics-like point of view on four-wave mixing. Using the model, the influence of threshold coupling strength and phase-conjugate reflectivity on transmissivity between the coupled interaction regions is investigated. The smaller transmissivity will decrease the phase-conjugate reflectivity under the same coupling constant and increase the threshold coupling constant. The output characteristics of bird wing MPPC are studied with experiment, and the dependence of phase-conjugate reflectivity of MPPC on the incident position is presented. An output characteristics model of bird wing MPPC with four coupled interaction regions is proposed, and simulation conclusions are in agreement with the experimental results.